New lantern from "scrap" parts

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jcs0001
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Location: western canada
New lantern from "scrap" parts

I bought a few 17mm driver’s and xre’s on 20mm bases some time ago. They were used to build several bike lights. I ended up with some left over and decided to make use of them.

Along with the above I had a box full of used electronic enclosures given me by a friend. They have holes and some bits and pieces inside but are easily cleaned up.

I was given a number of laptop batteries some time ago and dissembled them finding that they all had 17670’s inside. Most were “toast” however about 8 were ok – had decent voltage and capacities were close to the rated level.

Somewhere on the forum I noticed the use of a white film container as a diffuser for a lantern. Not sure where but most of the ideas for this light came from others – it isn’t very original.

I had hoped that I could mount a fenix diffuser above the led however the 20mm led is too large so I had to opt for plan 2 which was to use a film container. The container is a press fit over the led end of the aluminium slug.

A sample of used enclosures:

! photo IMG_1384.jpg!

Xre and driver:

! photo IMG_1385.jpg!

Cells:

! photo IMG_1383.jpg!

Finished product:

! photo IMG_1390.jpg!

I have a metal lathe and small mill so making the standoffs for the voltmeter and the switch were simple once I figured out what would work. The led sits on a solid piece of aluminium turned down so that the driver sits flush with the base. The aluminium and standoffs are epoxied onto the box with some epoxy left over from other projects.

There is very little heat cast from this – I’ve measured the aluminium slug and the led and they barely get warm. So far the unit has been running for almost three hours and the voltage of the two batteries (in parallel) is 3.59V.

If anyone has any ideas as to how to reduce the light output (and hopefully increase the run time) using the existing driver, I would appreciate it.

(more photos of the guts of this to follow – warning – it’s not pretty).

Thanks,

John.

I’ll add a bit further information in the next post.

jcs0001
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I’ve tried to get more info about the driver but it appears that dx.com does not carry it now. As I recall it was a single mode meant for somewhere between about 3 volts and 6 volts and put out about 700 ma. No info is available on the surface of the chips on the boards that I have.

A photo of the underneath of the aluminium slug:

! photo IMG_1392.jpg!

Cells and holders:

! photo IMG_1391.jpg!

The holders are cheap 18650 holders with rather fine wire. They are a bit short so I have cut them in the middle and epoxied the two ends so that the cells will fit.

The standoffs were made with some plastic pipe.

I don’t have any of the small lilion charge boards in stock right now but will eventually wire one of them in place so that the lantern becomes a usb rechargeable unit.

John.

LowLumen
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To lower the current draw of the driver; there should be a sense resistor near the negative lead to the LED. Change this resistor to a higher value to lower the current.

Welcome to the (very small) club of those who change sense resistors to LOWER current draw rather than raise it. Shocked
…I thought I was the only one who does such things.

jcs0001
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LowLumen:

Will take a look at this and see what I can do. I like bright lights but most of the time use the low modes. Moonlight is great.

Thanks for the info.

John.

LowLumen
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That driver looks like a variation similar to this one:

http://lygte-info.dk/review/DriverTest%20Anti-reverse%20Driver%20Board%2...

Note the sense resistor next to the black LED wire.
Figure out the formula to calculate R value for current based on what it is doing with the existing resistor. I = Constant/R

We are expecting a major storm here later in the week, with high winds and tall trees means possible power outages. Run times measured in many hours works best for this. Several lamps and lanterns of 100-300 lumen works better than one very bright that blows the battery in a few hours. Run time of 6+ to 20+ hours work best for me. I have enough to do without needing to change or charge batteries during such events.

I have bright battery burning lights too but they don’t get much use during power outs. For their intended use, lanterns should have long run times.

WarHawk-AVG
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Doesn’t the driver have modes?

If not, get a driver that has modes…then click the clicky to select the output level you want

Really nice build, very innovative, keep up the good work!

LowLumen
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I’ve done 2 modes with these single mode drivers using a separate switch for a parallel sense resistor. Desk light with high for task and low for ambient or longer run time.

djozz
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The first picture of the casings, and the mention of old-school XR-E's gave me a low expectation of the outcome, but then the picture of the finished light came: I love it and I want one too! Smile

jcs0001
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I could install a multi mode driver but wanted to make this with parts that I can’t use otherwise. As it is I expect about 5 hours of light without running the batteries down too much so may end up darkening the diffuser somehow. It is too bright although it does loose some lumenosity as the batteries come down in voltage.

I will also try to adding a resistor as that would be the most elegant method. If it wasn’t so cool in my shop I could always give it a coat of paint to make it look better Smile

If I could come across some kind of scrap piece that would make a better diffuser it would make it easy.

John.

DBSAR
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This is a cool & interesting build Smile nice job.

That Canadian flashlight guy & Lantern Guru -Den / DBSARlight

Fritz t. Cat
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WarHawk-AVG wrote:
Doesn’t the driver have modes?

If not, get a driver that has modes…then click the clicky to select the output level you want

Really nice build, very innovative, keep up the good work!


Most of us do use low modes sometimes, but the idea of not having a high mode at all really gets to us.

Flashlight designers should look at lighthouses and pottery.
这些谁设计的手电筒应该看灯塔,以及在陶器。